ESP-PROG is USB to Serial converter but beside the Serial TX and RX signals it also can power the target with +5V up to 0.5A or 3.3V up to 0.5A and have two additional signals which make programming automatic RESET (EN) and BOOT enable.
ESP-PROG-C includes all necessary cables for the ISP programming – 7 pcs jumper wires female to female and 6 pin ICSP cable.
ESP-PROG is based on CH340T IC and has drivers for Linux, Windows, MACOS, Android with up to 2 Mbps speed.
olimex 
May 29, 2020 @ 12:09:51
What are the settings necessary to make this programmer work in the Arduino and PlatformIO IDE’s ? The users manual has no indication about this.
Jun 26, 2020 @ 18:22:48
Playing with CH552T now (programmable chip), but some people complained about the inability to use the chip faster then 115200…